Wood charcoal was used in iron production up to about 1750. Charcoal works well but it would be too expensive to use in steel making. It takes about 100 kg of woods to make only 1 kg of steel. Regular coal was tried, but it did not work well due to impurities in the coal, especially sulfur, are transferred to the metal. Sulfur in iron makes it very weak. Thus, we need to convert the coal into coke by destructive distillation method so that many of the impurities would come out of the coal. It remains mostly pure carbon with high calorific value which we called "Coke". The coke is then acceptable for metallurgical purposes.

Unfortunately, since the beginning of the Industrial Revolution, the burning of fossil fuels like coke and coal has contributed to the increase in greenhouse gases in the atmosphere from 280 ppm to 390 ppm, which caused greatly affect to the Global Warming.

After UN Climate Change Conference (COP15) in Copenhagen 2009, steel industry in Brazil proposed to replace coal and coke with charcoal in their high temperature furnaces. The program "Green Steel for the Brazilian Steel Industry" converted wood from Eucalyptus plantations into charcoal that will be used in steel making. However, this effort unavoidably raised environmental concern about deforestation.

In 2010, Japan Consulting Institute took a bold action in search of a better, 'greener', and even cheaper alternative to replace fossil fuels like coke in steel making. The research revealed that Palm Kernel Shell charcoal(PKS charcoal) is proven to be a better fuel in Electric Arc Furnaces (EAF). As auxiliary energy in EAF, PKS charcoal simply outperforms coke. Because of the low sulfur and ash content and high calorific value, PKS charcoal can be said better fuel than coke, so we can consider PKS charcoal is the bio-coke. The test use in EAFs showed that no bad effect, which was concerned at first from high volatile matter, was observed. On the contrary, electrical energy saving was better than the case of coke from the high volatile content. In addition to that, as CO2 generated from the charcoal is not counted as Green House Gases, use of charcoal has the possibility of CDM project.The complete report on the research can be read here.

Another big advantage of using PKS charcoal is that the ash residue from combustion is not considered as hazardous waste. You can simply dump the ash for landfill without any environmental problem. On contrary, in many countries, ash from coal and coke combustion is considered as hazardous and toxic waste, due to heavy metal contents such as arsenic, lead, mercury, and selenium.

PKS Charcoal as Alternative Fuel in Steelmaking

Palm Kernel Shell charcoal has higher calorific value comparing to regular coke from coal. Calorific value is the most important characteristics of a good fuel. In an Electric Arc Furnaces, PKS charcoal can be used as auxiliary energy with ratio 25 kg of PKS charcoal for 1 tonne steel.

PKS Charcoal as Reducing Agent in Steelmaking

To extract metal from ore, you need reducing agent that has very high carbon content. Carbon will reduce oxygen from ore in very high temperature environment. For this purpose, we make PKS charcoal with fixed-carbon content higher than 80% so it's suitable as reductant in metallurgy.

PKS Charcoal as Carburizer in Steelmaking

Carburizing or carburising is a heat treatment process in which iron or steel absorbs carbon liberated when the metal is heated in the presence of a carbon bearing material, such as PKS charcoal, with the intent of making the metal harder. As carburizer, Palm Kernel Shell charcoal with high fixed-carbon should be granulated in powder form with size 1 - 5mm.

Characteristics Comparison Between PKS Charcoal and Coke in Steel Industry